No. 35. 

 TRIODIA GRANDIFLORA Vasey. 



Plant perennial, with tufted bullions base, rather glaucous or minutely cinerous- 

 pubescent throughout. 



Culms slender, erect, not branching, often geniculate at the hairy nodes, terete, 

 sparingly pubescent, 1 to 2 feet tall. 



Leaves; radical, numerous with compressed, equitant, hairy-fringed sheaths 

 and flat or folded, white-margined, pubescent, obtuse or abruptly pointed blades, 

 2 to 4 inches long; of culm 3, rarely 2 or 4; sheaths half as long as internode, 

 close, slightly pubescent or nearly glabrous; blades like those of radical leaves but 

 upper ones shorter and erect. 



Inflorescence a close, contracted, head-like white panicle, composed of numer- 

 ous, nearly sessile branches, 1 to 2 inches long; rachis and branches somewhat 

 pubescent, or scabrous. 



Spilcelets nearly sessile, oblanceolate, compressed, 4- to G-flower'ed, 2 lines wide, 

 4 to 5 lines long; first glume lance-ovate, acute, carinate, membranaceous, minutely 

 scabrous on keel, 1-nerved or sometimes 3-nerved on lower spikelets, 2 to 3 lines 

 long; second glume same, but ciliate at base, always 1-nerved, and 1 line longer; 

 floral glume lance-ovate, obtuse and' minutely ciliate, or with 2 narrow lobes at 

 apex, pubescent below, profusely ciliate, 3-nerved, 2 to 3 lines long; hispid mid- 

 nerve excurrent in an awn i to 1 line long; palet broadly lanceolate, pubescent at 

 the base and on the 2 prominent keels, 1 to li lines long. 



Grain not present in the specimens examined. 



Plate XXXV; a and b, floral glumes showing the extremes of variation at 

 the apices; c, palet. 



This species has been called T. avenacea H. B. K., from which it differs in its 

 much larger size, and in its flowers, as is shown by a comparison of the figure in 

 H. B. K. 



Western Texas to Arizona and Mexico. 



